Wireless communications devices, such as wireless terminals or wireless base stations, include wireless transceivers to perform wireless communications, such as radio frequency (RF) communications. A wireless transceiver commonly includes one or more filters, such as a band pass filter, a band reject filter, or other types of filters. A band reject filter is used to reject or attenuate signals having frequencies within a particular band, while allowing frequencies outside the band to pass through. A band pass filter, on the other hand, allows frequencies within a band to pass through, while rejecting or attenuating signals having frequencies outside the band. Other types of filters include low pass filters, high pass filters, and so forth.
Certain types of high performance filters use external impedance matching circuits that are connected to terminals of the filter. An “external” matching circuit refers to a matching circuit that is located outside a package of the filter. An issue associated with using external matching circuits is that impedances associated with electrical connecting structures between electronic circuitry inside the filter package and the external matching circuits can limit effectiveness of the filter at higher frequencies. Therefore, many conventional filters may not be effectively used in high-frequency wireless communications devices. Moreover, due to issues associated with external matching circuits, some high performance filters may simply omit the use of matching circuits for some terminals of the filters, which can come at the expense of reduced filter performance.